TheHollowNick

Ok so, I got a whole new exhaust, from the front pipe to the tail pipe.. Fired it up, and drove it around the block, the end of the cat near the muffler, was red hot.

My first question is, I tuned it before the new exhaust, could it be a misfire, I put the wires in the wrong place problem?

Also is the cat/muffler ruined now, It was no more then 5minutes of driving, and 10 minutes of idling... Really don't wanna have to buy another cat.

Also nothing is clogged, I checked and double checked before putting everything on.. Help is much obliged

96 4.0 Auto

belvedere

How does it run?

TheHollowNick

Idles fine, Then it drives as if its offbeat, and has hesitation..

salad

Sounds lean - any codes to be had? Your '96 should have OBD-II

hbracing13

Red hot after the cat? If it was before I say your cat it gone but you would get the rotten egg smell. Has it thrown CE light?

TheHollowNick

Investigating I found plug wires 2 and 3 were switched.. Would that cause a misfire and cause my cat to glow, and if that was the problem will i need a new cat? It was only that hot once

hbracing13

That would explain the missfire and off beat drive when driving. The pontiac quad4 engines would do the same if the coil pack housing was cracked aka the battleship. Would run idle fine but wouldn't allow you to go above 2k and would run like crap.

TheHollowNick

Yeah but could that cause a brand new cat to glow? the extra fuel being dumped into it right?

Glockmeister

I had a cat go bad and there was no rotten egg smell. I just had a misfire. Changed out cat and misfire went away.

Tom95YJ

Is the cat on facing the proper flow direction ?

Radi

That'll do it. Fix the plug wires and verify the problem is gone.
5-10 min running rich isn't going to kill it.